Steerable rear tractor suspension

Abstract

A steerable rear suspension for a tractor includes a chassis comprising a front end, a rear end, a left side and a right side; an engine mounted on the chassis; a pair of steerable front wheels coupled to the front end, left and right side of the chassis; a left rear suspension including a left rear suspension arm pivotally coupled to the chassis at a leading end of the suspension arm, and a first steerable planetary gear system mounted on a trailing end of the suspension arm; a right rear suspension including a right rear suspension arm pivotally coupled to the chassis at a leading end of the suspension arm, and a second steerable planetary gear system mounted on a trailing end at the right suspension arm; and left and right rear wheels driven by the first and second planetary gear systems.

1. A tractor, comprising;
 a chassis comprising a front end, a rear end, a left side and a right side; 
 an engine mounted on the chassis; 
 a pair of steerable front wheels coupled to the front end, left and right side of the chassis; 
 a left rear suspension including a left rear suspension arm pivotally coupled to the chassis at a leading end of the suspension arm, and a first steerable planetary gear system mounted on a trailing end of the suspension arm; 
 a right rear suspension including a right rear suspension arm pivotally coupled to the chassis at a leading end of the suspension arm, and a second steerable planetary gear system mounted on a trailing end of the right suspension arm; and 
 left and right rear wheels driven by the first and second planetary gear systems; 
 wherein each of the first and second planetary gear systems further comprises: 
 a first housing section bolted to an associated suspension arm; 
 a second housing section pivotally coupled to the first housing section to pivot about a substantially vertical axis; and 
 a third housing section rotatably supported on the second housing section and enclosing a planetary gear train; and 
 further wherein the third housing section supports three planet gears of the planetary gear train, and further wherein one of the axles is fixed to the third housing section to rotate therewith. 
 
   
   
     2. A tractor, comprising;
 a chassis comprising a front end, a rear end, a left side and a right side; 
 an engine mounted on the chassis; 
 a pair of steerable front wheels coupled to the front end, left and right side of the chassis; 
 a left rear suspension including a left rear suspension arm pivotally coupled to the chassis at a leading end of the suspension arm, and a first steerable planetary gear system mounted on a trailing end of the suspension arm; 
 a right rear suspension including a right gear suspension arm pivotally coupled to the chassis at a leading end of the suspension arm, and a second steerable planetary gear system mounted on a trailing end of the right suspension arm; 
 left and right rear wheels driven by the first and second planetary gear systems; and 
 an upper pivot joint and a lower pivot joint coupling a first housing section fixed to an associated suspension arm to a second housing section, each of the upper and lower pivot joints further comprising a cup shaped socket configured to support a cup shaped pin. 
 
   
   
     3. The tractor of  claim 2 , further comprising a ring gear carrier coupled to the second housing section to pivot therewith with respect to the chassis of the tractor, not to rotate. 
   
   
     4. A rear suspension for a tractor with a chassis, the suspension comprising;
 a rear suspension arm pivotally coupled to the chassis at a leading end of the suspension arm; 
 a first steerable planetary gear system mounted on a trailing end of the suspension arm; and 
 an axle extending from a housing of the planetary rear system; and 
 a large rear wheel coupled to the axle; 
 wherein the planetary gear system further comprises: 
 a first cylindrical housing section bolted to an associated suspension arm; 
 a second cylindrical housing section coupled to the first housing section to pivot about a substantially vertical axis, the second housing section supported a sun gear on a bearing for rotation; and 
 a third cylindrical housing section rotatably supported on the second housing section and enclosing a planetary gear train; 
 wherein the third housing section supports three planet gears of the planetary gear train for rotation, and further wherein the axle is fixed to the third housing section to rotate therewith. 
 
   
   
     5. A rear suspension for a tractor with a chassis, the suspension comprising:
 a rear suspension arm pivotally coupled to the chassis at a leading end of the suspension arm; 
 a first steerable plaretary gear system mounted on a trailing end of the suspension arm; and 
 an axle extending from a housing of the planetary gear system; 
 a large rear wheel coupled to the axle; and 
 further comprising an upper pivot joint and a lower pivot joint coupling a first housing section fixed to an associated suspension arm to a second housing section, each of the upper and lower pivot joints further comprising a cup shaped socket configured to support a cup shaped pin. 
 
   
   
     6. The rear suspension of  claim 5 , further comprising a ring gear fixed to the second housing section to pivot therewith with respect to the chassis of the tractor. 
   
   
     7. A steerable planetary gear system for an agricultural tractor, comprising:
 a planetary gear set including a sun gear, a ring gear, and a plurality of planet gears; 
 a first housing section configured to be mounted to the tractor, the first housing being generally cylindrical in shaped and configured to enclose a drive shaft; 
 a second housing section pivotally coupled to the first housing, the second housing being further configured to suppport a sun gear of the planetary gear set for rotation with respect to the second housing section, the second housing section also being configured to support a ring gear of the planetary gear system; 
 a third housing section supported for rotation on the second housing, the third housing section including axle extending therefrom; and 
 a pivot joint coupling the first housing section and the second housing section, wherein the pivot joint coupling includes an upper pivot joint and the lower pivot joint, each of the pivot joints further comprising a pin and a socket. 
 
   
   
     8. The system of  claim 7 , wherein the pins have a cup-shaped body and a flange that is fixed to and extends from the body, and further wherein the second housing section is configured to receive and support the upper and lower pins. 
   
   
     9. A steerable planetary gear system for an agricultural tractor, comprising:
 a planetary gear set including a sun gear, and a plurality of planet gears; 
 a first housing section configured to be mounted to the tractor, the first housing being generally cylindrical in shaped and configured to enclose a drive shaft; 
 a second housing section pivotally coupled to the first housing, the second housing being further configured to support a sun gear of the planetary gear set for rotation with respect to the second housing section, the second housing section also being configured to support a ring gear of the planetary gear system; and 
 a third housing section supported for rotation on the second housing, the third housing section including an axle extending therefrom; 
 wherein the first housing section further comprises: 
 a flange at one end to mount the planetary gear system to the tractor, 
 a conical section coupled to and extending from the flange, 
 a generally cylindrical transition section coupled to and extending from the conical section, and 
 a steering knuckle section coupled to and extending from the transition section. 
 
   
   
     10. A steerable planetary gear system for an agricultural tractor, comprising:
 a planetary gear set including a sun gear, a ring gear, and a plurality of planet gears; 
 a first housing section configured to be mounted to the tractor, the first housing being generally cylindrical in shaped and configured to enclose a drive shaft; 
 a second housing section pivotally coupled to the first housing, the second housing being further configured to support a sun gear of the planetary gear set for rotation with respect to the second housing section, the second housing section also being configured to support a ring gear of the planetary gear system; and 
 a third housing section supported for rotation on the second housing, the third housing section including an axle extending therefrom; 
 wherein the third housing section supports the plurality of planet gears for rotation.